Systems and methods for monitoring and controlling fuel systems

ABSTRACT

Systems and methods may be provided for monitoring a fuel level of a vehicle. The fuel may be a gaseous fuel, such as natural gas. An electronic control unit may be able to receive a signal from one or more sensors. The electronic control unit may provide a command to drive a fuel gauge to display the fuel level. The electronic control unit may determine the gauge command based on the received signal and a filling compensation scheme. The electronic control unit may be initialized through a user interface. A filling compensation scheme may be selected during initialization. The electronic control unit may be capable of communicating various sensors, gauges, devices, controls and/or other ECUs of varying specifications.

CROSS-REFERENCE

This application a continuation application of U.S. application Ser. No.13/708,662, filed on Dec. 7, 2012, which claims the benefit of U.S.Provisional Patent Application Ser. No. 61/568,120, filed Dec. 7, 2011,which applications are incorporated herein by reference in theirentirety.

BACKGROUND OF INVENTION

Natural gas is a consideration as an alternative fuel for vehicles. In anatural gas-powered vehicle, a vehicle operator should be able to readfrom a fuel gauge a measure of fuel in the vehicle to obtain an accuraterepresentation of the remaining energy content of the vehicle, and thusthe remaining driving range of the vehicle.

Challenges remain for providing an accurate read of the remaining fuelin changing conditions (e.g., changing temperatures). Furthermore,different vehicles may utilize different sensors and gaugeconfigurations. Another concern for high pressure natural gas may besafety during fueling. Additionally, concerns for leakage andservice/maintenance of the vehicle may be provided.

A need exists for improved systems and methods for monitoring a fuellevel that may be able to compensate for various conditions. A needexists for a controller that may be able to assist with monitoring afuel level, and that may be able to operate with various sensors andgauge configurations. A need exists for systems and methods that improvesafety and life of the vehicle and/or vehicle fuel system.

SUMMARY OF INVENTION

Systems and methods may be provided for monitoring a fuel level of avehicle. The fuel may be a gaseous fuel, such as natural gas. Anelectronic control unit may be able to receive a signal from one or moresensors. The electronic control unit may provide a command to drive afuel gauge to display the fuel level. The electronic control unit maydetermine the gauge command based on the received signal and a fillingcompensation scheme. The electronic control unit may be initializedthrough a user interface. A filling compensation scheme may be selectedduring initialization. The electronic control unit may be capable ofcommunicating with various sensors, gauges, devices, controls and/orother ECUs of varying specifications.

An aspect of the invention may be directed to a method for monitoringgaseous fuel level comprising: receiving, at an electronic control unit,at least one signal from one or more sensors configured to monitor acondition of a gaseous fuel containing device; receiving, at theelectronic control unit, a selected filling compensation scheme chosenfrom a plurality of filling compensation schemes; and based on the atleast one signal and the selected filling compensation scheme, sending asignal to a gauge, thereby causing the gauge to display the gaseous fuellevel.

Another aspect of the invention may provide a method for initializing anelectronic control unit, said method comprising: connecting theelectronic control unit to one or more sensors configured to monitor acondition of a gaseous fuel containing device; connecting the electroniccontrol unit with one or more initialization device having a displayshowing a user interface; entering, via the user interface,specifications for the one or more sensor.

A further aspect of the invention relates to a vehicle control systemcomprising: a gaseous fuel containing device of the vehicle; anelectronic control unit capable of communicating one or more data withone or more entities on the vehicle and/or remote from the vehicle,wherein the entities include a sensor, a gauge and at least one of thefollowing: a control, another electronic control unit, a device, or aninformation system hosted on a device, wherein the electronic controlunit is configured to enable logging and acquisition of the communicateddata, and wherein the communicated data express a condition, a state oran instruction regarding a condition or a state of the gaseous fuelcontaining device.

Aspects of the invention may be directed to safety of the vehicle duringfueling. One, two, three or more switches may be provided to check thatthe fuel dispenser is disconnected from a receptacle by preventingengine cranking. Such switches may optionally not use relays. Suchswitches may be spark proof

Aspects of the invention further address gas leakage. Gas leakage may bedetected, and an alarm may be sent to the driver. This may assist withmaintenance and the proper operation of the system. An alert may also beprovided for a defined period (e.g., cycle of filling) to the driver, tocheck or repair the system. The service alert may assist with themaintenance and safety of the fuel system. It is beneficial for highpressure tanks that have limited life to check on their status atappropriate times, such as filling cycle.

Additional aspects and advantages of the present disclosure will becomereadily apparent to those skilled in this art from the followingdetailed description, wherein only illustrative embodiments of thepresent disclosure are shown and described. As will be realized, thepresent disclosure is capable of other and different embodiments, andits several details are capable of modifications in various obviousrespects, all without departing from the disclosure. Accordingly, thedrawings and description are to be regarded as illustrative in nature,and not as restrictive.

INCORPORATION BY REFERENCE

All publications, patents, and patent applications mentioned in thisspecification are herein incorporated by reference to the same extent asif each individual publication, patent, or patent application wasspecifically and individually indicated to be incorporated by reference.

BRIEF DESCRIPTION OF DRAWINGS

The novel features of the invention are set forth with particularity inthe below. A better understanding of the features and advantages of thepresent invention will be obtained by reference to the followingdetailed description that sets forth illustrative embodiments, in whichthe principles of the invention are utilized, and the accompanyingdrawings of which:

FIG. 1 shows an example of an electronic control unit (ECU).

FIG. 2 shows an example of an ECU within a fuel monitoring system.

FIG. 3 shows an example of an ECU within a vehicle.

FIG. 4 shows an example of an ECU control box. FIG. 4A provides aperspective view of the control box. FIG. 4B provides a top view of thecontrol box. FIG. 4C shows a side view of the control box. FIG. 4D showsa side view of another side of the control box.

FIG. 5 shows an example of method of performing initial, calibration, ormaintenance steps with the ECU.

FIG. 6 shows an example of connections for an ECU to a vehicle.

FIG. 7 shows an example of method of performing initial, calibration, ormaintenance steps with the ECU.

FIG. 8 shows an example of an ECU in communication with aninitialization device.

FIG. 9 shows an example of a user interface for fuel gauge set-up.

FIG. 10 shows an example of a method for displaying a fuel level usingan ECU.

FIG. 11 shows examples of entities in communication with an ECU.

DETAILED DESCRIPTION OF INVENTION

While preferred embodiments of the invention have been shown anddescribed herein, it will be obvious to those skilled in the art thatsuch embodiments are provided by way of example only. Numerousvariations, changes, and substitutions will now occur to those skilledin the art without departing from the invention. It should be understoodthat various alternatives to the embodiments of the invention describedherein may be employed in practicing the invention.

The invention provides systems and methods for monitoring fuel levels inaccordance with aspects of the invention. Various aspects of theinvention described herein may be applied to any of the particularapplications set forth below or for any other types of gaseous fuelmonitoring systems. The invention may be applied as a standalone systemor method, or as part of a vehicle or other system that utilizes gaseousfuel. It shall be understood that different aspects of the invention canbe appreciated individually, collectively, or in combination with eachother.

FIG. 1 shows an example of an electronic control unit (ECU) 100 inaccordance with an embodiment of the invention. The ECU may be incommunication with one or more sensors 102 and one or more gauges 104.

A sensor 102 may be in communication with a gaseous fuel containingdevice. The sensor may be a pressure sensor, temperature sensor,accelerometer, optical sensor, shock sensor, damage sensor, acousticsensor, or any other type of sensor. Examples of types of pressuresensors may include a piezoresistive strain gauge, capacitive pressuresensor, electromagnetic pressure sensor, piezoelectric pressure sensor,optical pressure sensor, potentiometric pressure sensor, resonantpressure sensor, thermal pressure sensor, and/or ionization pressuresensor. In some embodiments, the pressure sensors may have ratiometricvoltage output of about 0 to 5 volts. An example of a temperature sensormay include a variable resistance sensor, thermocouple, thermometer, orany other temperature sensor. In some embodiments, the temperaturesensors may have ratiometric voltage output of about 0 to 5 volts. Insome embodiments, a transducer may be provided (e.g., for pressure andtemperature) that may provide an electronic signal to the ECU. In someembodiments, a plurality of sensors may be in communication with theECU. The plurality of sensors may be the same type of sensors, or mayinclude different types of sensors. For example one or more temperaturesensors and one or more pressure sensors may be in communication withthe ECU.

One or more sensors 102 may be in communication with the ECU 100. Theone or more sensor may be connected to the ECU. For example, the one ormore sensor may be connected to the ECU via three or more lines (e.g.,positive, negative, signal). When a plurality of sensors are integrated(e.g., pressure and temperature), positive and negative powers may becommon. One or more voltage send line may be provided (e.g., 5 volt sendline), and one or more return data line may be provided. In one example,a temperature sensor may be coupled to the ECU via three or more lines(e.g., +5 V, −5 V, signal) and may provide a signal on a data lineindicative of the temperature of the natural gas in a gaseous fuelcontaining device, or the temperature of the gaseous fuel containingdevice, or the temperature of one or more plumbing lines, or the ambienttemperature. In some instances, a separate sensor may be provided forambient temperature. For example, a sensor on the ECU board, such as achip temperature sensor may be provided. In an alternate embodiment, asensor may communicate with the ECU wirelessly.

The ECU 100 may receive one or more signal from the one or more sensors102. The ECU may be responsive to the signals from the sensors, and maydetermine a command to send to a gauge 104. The command to the gauge maybe indicative of the amount of fuel remaining in the gaseous fuelcontaining device. The ECU may comprise one or more circuit that mayfilter one or more signal. For example, the ECU may comprise a circuitthat may filter a received signal (e.g., from a sensor), or filter asignal that is to be output (e.g., to a gauge).

The ECU may contain a printed circuit board with embedded (configurable)programmed logic. The ECU may contain memory. The memory may containtangible computer readable media such as code, logic, instructions forperforming one or more steps. These may include steps in accordance withone or more algorithm that may determine a fuel level based on receivedsignals. One or more calculation may be performed based on receivedsignals and/or stored data. Such calculations may utilize a gas law. Thecalculations may take the non-linearity of gas compressibility intoaccount. In some alternate embodiments, a memory may store a look-uptable that may include one or more gauge command provided based onsensor input. Alternatively no look-up table for gauge commands based onsensor input is provided. The ECU may contain one or more processor. Theone or more processors may be microprocessors. The microprocessors maybe useful to determine a command to be sent to the gauge depending oninput received at the ECU. The microprocessors may perform one or moresteps as dictated by non-transitory computer readable media stored inmemory. A microcontroller and interface software may be provided. Theinterface software may run on the ECU or an initialization device.

The ECU may have a housing, such as a plastic enclosure. The ECU mayhave electrical plugs that may provide connection interfaces with one ormore other devices.

The ECU 100 may be in communication with a gauge 104. The ECU may beconnected to the gauge. For example, the ECU may be connected to thegauge via a line. In one example, a temperature sensor may be coupled tothe ECU via two, three, or more lines and may provide a signal on a dataline indicative of the temperature of the natural gas in a gaseous fuelcontaining device, or the temperature of the gaseous fuel containingdevice, or the temperature of one or more plumbing lines, or the ambienttemperature. In an alternate embodiment, an ECU may communicate with thegauge wirelessly.

Any type of gauge 104 may be utilized in accordance with embodiments ofthe invention. The gauge may be capable of receiving a command from theECU, and based on said command, displaying a fuel level. The fuel levelmay be displayed via a rotating spindle, as a sliding needle, digitally,as an image, as an audio indicator, or any other visual or audioindicator. The fuel level may be displayed in volume measurements (e.g.,gallons or liters remaining), percentages (e.g., 67% of fuel left),status (e.g., full, empty), fraction (e.g., ⅓ remaining), or any units(e.g., 5 out of 10 bars full).

FIG. 2 shows an example of an ECU 200 within a fuel monitoring system.One or more sensors, such as a temperature sensor 202, pressure sensor204, or any other type of sensor such as those described elsewhereherein, may be in communication with the ECU. The sensors may beconnected to a gaseous fuel containing device 210. In some embodiments,a temperature sensor and/or pressure sensor may be capable of detectingthe temperature and/or pressure, respectively, of the gaseous fuelwithin the fuel containing device, the device itself, or ambientconditions. In one example, the temperature sensor may detect atemperature within the gaseous fuel containing device, and the pressuresensor may detect a pressure within the gaseous fuel containing device.

A gaseous fuel containing device 210 may be a tank, container, orvessel. The gaseous fuel containing device may be capable of containinga gaseous fuel, such as natural gas, therein. Any reference to gaseousfuel may include natural gas. This may include liquefied natural gas(LNG) or compressed natural gas (CNG). A gaseous fuel may includehydrogen or hydrogen based gas, hythane, H2CNG, or any other gas. Anyreference to gaseous fuel may include a fuel stored as a compressed gas,as a liquefied gas or as a liquid under its own vapor pressure,including, but not limited to, compressed natural gas (CNG), liquefiednatural gas (LNG), liquefied petroleum gas (LPG), Diesel fuel, gasoline,dimethyl ether (DME), methanol, ethanol, butanol, Fischer-Tropsch (FT)fuels, hydrogen or hydrogen-based gas, hythane, HCNG, syngas and/orother alternative fuels or fuel blends.

In some embodiments, a temperature sensor 202 and a pressure sensor 204may be connected to the ECU 200 via wired connections 222, 224. Forexample, the temperature sensor may be connected to the ECU via one,two, or more lines. The pressure sensor may be connected to the ECU viaone, two, or more lines. Any sensor, such as those described elsewhereherein, may be connected to the ECU via one, two, or more lines.Alternatively, one or more sensors, such as the temperature sensorand/or pressure sensor, may be connected to the ECU wirelessly.

The ECU 200 may be connected to a gauge 230. An example of a gauge maybe a two coil air core gauge. The two coil air core gauge may comprisecoils 232 and 234 wound substantially perpendicular to each other on abobbin (not shown) around a rotatable magnetic rotor 236. As current isprovided to the two coils of the air core gauge 230, the two coils maycreate a composite magnetic vector having a direction to which themagnetic rotor 236 rotates to align itself. A spindle (not shown) may beattached to the rotor and may rotate with the rotor. Pointer 240 may bestaked to the spindle, in a manner well known to those skilled in theart, and rotates with the spindle and rotor 236 to indicate, togetherwith display graphics 242, a measure of fuel in the gaseous fuelcontaining device 210. The gauge indication may be representative of thepercentage that the tank is full of natural gas, e.g., F (Full), ½ (50%full), E (empty), or any other fuel level display as described elsewhereherein.

The command on line 250 may vary the voltage at the junction of coils232 and 234, varying the ratio of the voltages across coils 232 arid234. In response to the changing voltage ratio across coils 232 and 234,current through the coils may change, changing the magnitudes of themagnetic fields created by the two coils and the direction of theresultant composite magnetic vector to which the rotor 236 may rotate(rotating the spindle and pointer) to align itself.

Lines 250 and 252 may provide feedback of the actual voltages across thecoils of the gauge 230 for closed loop control of gauge 230 in themanner described below.

A two coil air core gauge is provided by way of example only. Othergauges known in the art may be used. For example, various gauges may bedriven by the ECU.

FIG. 3 shows an example of an ECU 300 within a vehicle 350, provided inaccordance with an embodiment of the invention. The ECU may be mountedon the vehicle or within the vehicle. The ECU may travel with thevehicle.

A vehicle 350 may be any type of vehicle known in the art. A vehicle maybe a truck, such as a light duty truck (e.g., class 1, class 2 or class3), medium duty truck (e.g., class 4, class 5 or class 6), or heavy dutytruck (e.g., class 7 or class 8). In some embodiments, the vehicles maybe cars, wagons, vans, buses, high-occupancy vehicles, dump trucks,tractor trailer trucks, or any other vehicles. The same ECU may becapable of interacting with various vehicles or types of vehicle. Forexample, an ECU may be mounted onto a dump truck, and the same ECU maybe capable of being mounted on a bus.

A vehicle 350 may be propelled by a fuel. The fuel may be a gaseousfuel, such as natural gas. The fuel may be contained within a gaseousfuel containing device 310, such as a tank, vessel, or any other type ofdevice capable of containing a gaseous fuel. Any description herein of afuel tank, vessel, or any other type of gaseous fuel containing devicemay be applicable to any other type of gaseous fuel containing device.The gaseous fuel containing device may be capable of containing a fuelwith a certain amount of pressure. For example, the gaseous fuelcontaining device may be capable of containing a fuel having less thanor equal to about 10000 psi, 8000 psi, 7000 psi, 6500 psi, 6000 psi,5500 psi, 5000 psi, 4750 psi, 4500 psi, 4250 psi, 4000 psi, 3750 psi,3500 psi, 3250 psi, 3000 psi, 2750 psi, 2500 psi, 2000 psi, 1500 psi,1000 psi, 500 psi, 300 psi, 100 psi, or less.

A gaseous fuel containing device 310 may have one or more fuel output312. The fuel output may transfer the fuel to another part of thevehicle 350, such as an engine. In one example, the fuel may be outputto mix with air in the cylinder of an engine. The fuel may be used inthe process of propelling the vehicle.

In some embodiments, a vehicle 350 may contain a single gaseous fuelcontaining device, such as a tank 310. In other embodiments, the vehiclemay contain a plurality of tanks. The tanks may or may not have the samecharacteristics. In some embodiments, the conditions of a single tank orthe fuel within the tank may be monitored by a single ECU 300.Alternatively, the conditions of a plurality of tanks or the fuel withinthe tanks may be monitored by a single ECU. Alternatively, a pluralityof ECUs may be used to monitor a single tank (and/or fuel within thetank), or a plurality of tanks (and/or fuel within the tanks).

An ECU 300 may receive signals from one or more sensors 302, 304, 306.The sensors may be within a tank 304, attached to a tank 304, and/orseparate from the tank 306. In some examples, a temperature sensorwithin a tank may capture the temperature of the fuel within the tank. Apressure sensor within a tank may capture the pressure of the fuelwithin the tank. A temperature sensor attached to the tank may capturethe temperature of the tank. The temperature sensor separate from thetank may capture ambient conditions around the tank and/or thetemperature of one or more plumbing lines. Any number or combination ofsuch sensors may be used. Any number of sensors or combinations of suchsensors may be used for a single tank, or for a plurality of tanks.

The ECU 300 may communicate one or more command to a gauge 330. Thecommand may be provided directly or indirectly to the gauge. One or moreadditional device may be provided which may convert the proper signalfor the gauge. The command to the gauge may be generated based on thesignals from one or more of the sensors. The gauge may display a levelof fuel. The level of fuel may be for a single tank. The level of fuelmay be the overall fuel within the vehicle, which may be distributedover one or more tanks. Alternatively, the level of fuel may be shownseparately for each tank of the vehicle. In one example, the gauge maybe display the fuel level on a dashboard of the vehicle.

In embodiments with multiple tanks gaseous fuel containing devices(e.g., tanks), one or more sensors may be provided per each gaseous fuelcontaining device. For example, a first set of temperature and pressuresensors may be provided to monitor temperature/pressure of a first tank,and a second set of temperature and pressure sensors may be provided tomonitor temperature/pressure of a second tank.

The ECU may be capable of communicating with various types of sensorsand/or gauges. The ECU may be able to compensate for differentcharacteristics of sensors and/or gauges. The ECU may be initialized tooperate with a particular set of sensors and/or gauges. The ECU may bere-initialized and/or programmed to operate with a different set ofsensors and/or gauges. A user may select characteristics or parametersof the various sensors and/or gauges, thereby enabling the ECU tointeract and provide an accurate fuel level reading for the sensorsand/or gauges. In some instances, the characteristics or parameters ofthe various sensors and/or gauges may be automatically detected andupdated when the ECU is placed into communication with the sensorsand/or gauges.

FIG. 4 shows an example of an ECU control box 400 in accordance with anembodiment of the invention. FIG. 4A provides a perspective view of thecontrol box. The control box may have a cover 410, which may be ahousing, shell, or enclosure.

One or more control box interfaces 420, 422, 424 may be provided. Thecontrol box interfaces may permit the control box to be connected to oneor more other devices or sensors. The control box may be electricallyconnected to the one or more other devices or sensors. For example, aninitialization control box interface 420 may permit the control box tobe connected to an initialization device. A sensor interface 422 maypermit the control box to be connected to one or more sensors of avehicle. A gauge interface 424 may permit the control box to connect toa gauge.

A control box may have one or more attachment features 430 that maypermit the control box to be attached to a vehicle in a desired manner.For example, a control box may be screwed onto a surface of a vehicle. Acontrol box may be attached to a vehicle in any manner known in the art,such as screwing, riveting, welding, soldering, brazing, adhesives,interlocking features, hook and loop fasteners, ties, clamps, or anyother attachment techniques. The control box may be permanently attachedto the vehicle. Alternatively, the control box may be removably attachedto the vehicle. The control box may be attached to an exterior surfaceof the vehicle. In some embodiments, the control box may be providedwithin a compartment or section of the vehicle. A cover may be providedover the control box. The control box may or may not be exposed.

FIG. 4B provides a top view of the control box. The control boxinterfaces 420, 422, 424 may be disposed anywhere on the control box.The control box interfaces may be provided on a surface of the controlbox cover 410. The control box interfaces may be provided at or nearedges or sides of the control box. The control box interfaces may all beprovided on the same surface or side of the control box cover, or may beprovided at different surfaces or sides of the control box cover.

A control box interface may have one or more electrically connectingportion 426, 428. For example, an electrically connecting portion may bea pin 426 that may protrude, or a hole 428 that may be configured toreceive a pin. When a pin is inserted into a hole, an electricalconnection may be made. Any other electrical connection mechanisms maybe used.

The control box interfaces may be shaped to connect with a connectorfrom a respective device. For example, a sensor interface 422 may beconfigured to receive a connector (e.g., cable, wire, plug, adaptor)from a sensor.

A control box may have any dimensions or shape. In one example, acontrol box may have a quadrilateral cross-section with a width W and alength L. A control box may have any other shape, such as a circle,ellipse, pentagon, hexagon, or octagon. A dimension of the control box,such as a width, length, diagonal, or diameter, may have any value,which may be greater than, less than, equal to one or more of thefollowing, and/or fall between two or more of the following: 1 mm, 1 cm,1.5 cm, 2 cm, 2.5 cm, 3 cm, 4 cm, 5 cm, 6 cm, 7 cm, 8 cm, 9 cm, 10 cm,12 cm, 15 cm, 20 cm, 25 cm, 30 cm, or 50 cm.

FIG. 4C shows a side view of the control box. A connection interface420, 422, 424 may protrude or extend from the control box cover 410. Inalternate embodiments, the connection interface may be flush with thecover, or may be depressed within the cover. In alternate embodiments, acontrol box may communicate with another device (e.g., sensor, gauge,initialization device) wirelessly. A wireless communication module,which may permit such communications, may be provided within the housingof the control box, or on the housing of the control box. Anycombination of connection interface configurations may be used.

FIG. 4D shows a side view of another side of the control box. Aspreviously described, a connection interface 420, 422, 424 mayoptionally protrude from the control box cover 410. Space may or may notbe provided between the connection interfaces. A control box cover mayhave any height h which may be greater than, less than, equal to one ormore of the following, and/or fall between two or more of the following:1 mm, 3 mm, 5 mm, 7 mm, 1 cm, 1.2 cm, 1.5 cm, 2 cm, 2.5 cm, 3 cm, 3.5cm, 4 cm, 5 cm, 6 cm, 7 cm, 8 cm, 9 cm, or 10 cm. A connection interfacemay extend from the surface by any amount e which may be greater than,less than, equal to one or more of the following, and/or fall betweentwo or more of the following: 1 mm, 3 mm, 5 mm, 7 mm, 1 cm, 1.2 cm, 1.5cm, 2 cm, 2.5 cm, 3 cm, 3.5 cm, 4 cm, 5 cm, 6 cm, 7 cm, 8 cm, 9 cm, or10 cm. The extension of an interface may be greater than, less than, orequal to about the height of the control box.

FIG. 5 shows an example of a method for performing initial, calibration,or maintenance steps with the ECU in accordance with an embodiment ofthe invention. In some instances, initialization may occur prior to theoperation of a vehicle. Initialization may occur while a vehicle is off(e.g., key off). Alternatively, initialization may occur while a vehicleis on or in operation.

An ECU may be connected to an initialization device 510. Examples of aninitialization device may include a personal computer, such as a desktopor laptop computer, server, tablet, mobile device (e.g., smartphone,cellular phone, personal digital assistant, pager), or any other devicethat may be capable of performing an initialization of the ECU.

The ECU may be connected to the initialization device via a wiredconnection, or wirelessly. In one example, a cable, wire, plug, oradaptor may be used to connect the ECU to the initialization device. Forexample, the ECU may be connected to the initialization device via a USBto TTL Serial cable (e.g., with a DB9 connector). The ECU may or may notbe receiving power from the initialization device.

The ECU may also be connected to a vehicle 520. The ECU may be connectedto the vehicle at any time, e.g., the ECU may be connected to thevehicle before being connected to the initialization device, after beingconnected to the initialization device, or simultaneously with beingconnected to the initialization device. The ECU may be connected to thevehicle via a wired connection, or wirelessly. In one example, a cable,wire, plug, or adaptor may be used to connect the ECU to theinitialization device. For example, the ECU may be connected to theinitialization device via an SAE J1128-18 AWG or automotive wires 18AWG.

The ECU may be connected to the vehicle and may provide communicationwith one or more portion of the vehicle. For example, the ECU may beelectrically communicating with a sensor of the vehicle. The ECU may beelectrically communicating with a gauge of the vehicle. In someexamples, the ECU may be electrically connected to a sensor of thevehicle and electrically connected to a gauge of the vehicle, the ECUmay be electrically connected to the sensor without being electricallyconnected to the gauge, electrically connected to the gauge withoutbeing electrically connected to the sensor, or not electricallyconnected to the sensor and not electrically connected to the gauge. TheECU may be electrically connected to the vehicle and may or may notreceive power from the vehicle. An example of an electrical connectioninterface for the ECU is provided in FIG. 6 which will be described ingreater detail below.

One or more initialization step 530 may occur involving the ECU. Aninitialization device may send one or more instructions to the ECU toperform the initialization step. The initialization device may receiveinformation from the ECU (e.g., information received from a sensorand/or gauge of the vehicle, or provided to a gauge of the vehicle). Theinitialization device may be capable of two-way communications with theECU. An initialization device may include a user interface that maydisplay collected information, and/or accept a command from a user.

Examples of initialization steps may include setting up a fuel gauge532, performing diagnostics 534, checking version of installed software536, or updating the firmware of the ECU 538. Such initialization stepsmay be performed while a vehicle is not in operation. Alternatively, oneor more of the steps may be performed while the vehicle is in operation.Such initialization steps may be performed periodically, or upon adetected event. Such initialization steps may provide initial,calibration, or maintenance steps with the ECU.

Setting up a fuel gauge 532 is described in further detail elsewhereherein. Setting up a fuel gauge may include determining a fillingcompensation scheme. A filling compensation scheme may be selected froma plurality of options. Setting up a fuel gauge may assist withpermitting an ECU to accurately provide a fuel level to a gauge. Thismay be performed by determining characteristics and/or parameters ofvarious sensors and/or gauges. This may permit an accurate or desiredfuel level to be displayed on the gauge, for various gaugeconfigurations or sensor configurations. The ECU may be able to adaptfor different sensors and/or gauges.

Performing diagnostics 534 may include receiving one or more signalthrough the ECU. The signals received from the ECU may include signalsreceived from one or more sensors. For example, diagnostics may testwhether pressure and temperature sensor wires are correctly connected.The diagnostics may determine whether one or more wires of the sensorsare disconnected (e.g., open circuit). The diagnostics may alsodetermine whether there is a short circuit for the sensor wires.

In addition to checking the sensors, a calibration file name may bechecked. Parameters may be checked based on reading pressure andcomparing it with a mechanical pressure sensor. Furthermore a gauge maybe checked. Signals received may be checked with the dash gauge reading.

Checking the version of the installed software 536 may include running aprogram which may check the version of the software installed on theinitialization device. In an alternative embodiment, checking theversion of installed software may also check on a program which may beprovided or installed on an ECU. In some embodiments, if updates to thesoftware are available, an option may be provided to update thesoftware. An update to the software may be automatically initiated, ormay await user confirmation prior to occurring.

In some embodiments, the latest version of firmware on the ECU may bechecked and/or displayed.

Updating the firmware of the ECU 538 may include uploading a new updatedfirmware to the ECU. This may occur after adding or modifying a softwareon an initialization device. The new firmware may be delivered throughthe initialization device to the ECU. Alternatively, additional devicesmay be used to deliver new firmware to the ECU. In one example, an AVRISP programmer, compatible with Amtel STK-300 (development board), forinstance AVR ISP-U or AVR-ISP500, and/or AVR software may be used.

FIG. 6 shows an example of connections for an ECU to a vehicle. Suchconnections are provided by way of example only. The locations and/ororders of the connections may be varied.

A sensor connection interface 610 may be provided. A first connection612 may receive a signal from a temperature sensor, and a secondconnection 614 may receive a signal from a pressure sensor. Any numberof connections may be provided, corresponding to any number or types ofsensors. A third connection 616 may be provided for power (e.g., +5V, orany other voltage value), and a fourth connection 618 may be providedfor ground.

A gauge connection interface 620 may be provided. The interface mayinclude a gauge ground 622 and gauge live 624 connection. A signal maybe provided to the gauge from the ECU and/or received by the ECU fromthe gauge through such connections. The interface may further include akey start connection 626, key on connection 628, a start solenoidconnection 630, and/or a key/solenoid ground connection 632. Suchconnections may be useful for determining whether a vehicle is inoperation or not (e.g., whether a key has been turned in an ignition). Asolenoid connection may activate a high pressure solenoid valve in orderto start an engine or feed the engine of a vehicle. One or more kill capconnections, such as a first kill cap connection 634, second kill capconnection 636, and/or third kill cap 638 connection may also beprovided. Kill caps may be safety switches, so if their signals are notok (e.g., not in an acceptable range), the ECU may not allow the engineto be cranked. This may be a safety matter for fueling a vehicle, whenthe dispenser is connected to a gas tank of the vehicle. One or morepower and ground connections 642, 644, 646, 648, 650, 652 may also beprovided. Optionally, a lamp connection 640 may be included. The lampmay be a low fuel warning lamp. When the amount of fuel is lower than aspecified amount, the ECU may turn the lamp on. The lamp may also beused for providing an alert to a driver for leakage (e.g., blinkinglight) and service alarm (e.g., slower blinking light). Alternatively,other alert mechanisms may be used. The lamp may be integrated in thedash gauge or in a cluster.

FIG. 7 shows an example of a method for performing initial, calibration,or maintenance steps with an ECU in accordance with an embodiment of theinvention. An ECU may be connected to an initialization device 710. TheECU may be connected to the initialization device in any manner, asdescribed elsewhere herein.

A fuel gauge set-up 720 may occur. Setting up the fuel gauge may includeone or more of the following steps: selecting a filling compensationprocedure 722, selecting transfer function specifications 724, selectingsensor specifications 726, and selecting a service cycle 728. Thesesteps may occur in any order or may have a predetermined order. Any ofthese steps may be optional or additional steps may be provided.

Selecting a filling compensation procedure 722 may include selecting afilling compensation scheme from a plurality of possible fillingcompensation schemes. For example, one, two, three, four or more optionsmay be provided for filling compensation schemes. A filling compensationscheme may be selected from the plurality. Examples of possible fillingcompensation schemes may include none, temperature-based compensation,fuel-based compensation, or time-based compensation. A plurality offilling compensation schemes include two or more of the following: nospecial correction measurements; gas pressure compensated based onambient temperature; compensation based on filling speed and keepingmaximum pressure and reducing it by fuel consumption up to thresholdpressure; compensation based on filling and reducing the pressure by thetime when the key is on. A filling compensated may be provided whenfilling the tank with fuel, or after the vehicle has been fueled and isin operation.

When the “none” option (e.g., no special correction measurements option)is selected, the ECU may just take the true pressure sensor values, andbased on those values send a command to the gauge. For example,regardless of the temperature or other conditions, a pressure readingfrom one or more pressure sensor may be utilized as the pressure valuefor the gaseous fuel tank. For example if Pg is the pressure sent to thegauge, Ps is the gas pressure from the sensor, Pg=Ps.

When a temperature-based compensation is selected, gas pressure may becompensated based on temperature. This may be the temperature measuredwithin a tank, the temperature of the tank, the temperature of one ormore plumbing lines, or ambient temperature external to the tank. Forexample, as the temperature changes throughout the day, this may causethe pressure of the gas within the tank to change, even if the amount ofavailable energy (e.g., gas) is not changing. In one instance, if thetemperature, e.g., ambient temperature is Ta, and a gas temperature isTs, if Ta<=Ts, then Pg=Pt, where Pt is the compensated gas pressurebased on ambient temperature. If Ta>Ts, then Pg=Ps. In another instance,Pg=Pt regardless of relative temperature conditions. The compensated gaspressure Pt may be calculated based on the ideal gas law (e.g., PV=nRT).For example, Pt may be calculated as follows:

Pt=Ps×(Ta+273.15)/(Ts+273.15)

With a fuel-based compensation, the ECU may compensate based on fillingspeed. This may occur when keeping maximum pressure and reducing it byfuel consumption up to “threshold pressure.” In one summary example,Pg>Pt when Pt>threshold, and Pg=Pt when Pt<=threshold, where Pg=pressuresent to gauge, Pt=ambient temperature compensated pressure.

The maximum pressure Pmax from the last filling may be saved in thememory of the ECU, and the ECU may send the maximum pressure to thegauge. In one example, FIG. 9 provides a value of 3600 psi for the Pmax.During gas consumption, the ECU may compensate the pressure by a factorof deviation from a threshold value. The threshold value may be providedon a user interface and may be entered by a user or may be generatedautomatically or based on a measurement. A default threshold value maybe offered. The default threshold value may or may not depend on one ormore selected or measured values. For example, FIG. 9 provides anexample where the threshold value is 3000 psi.

When the tanks are filled rapidly and gas temperature inside the tanksincrease, after some time has passed if no fuel is consumed, the gastemperature and gas pressure within the tanks may drop. This may lead toan operator of a vehicle erroneously thinking that there is a leak inthe system because of the pressure/temperature drop without gasconsumption. However, this drop may be due to temperature drop afterrapid filling. Alternatively, temperature/pressure drop may occur withdrop in ambient temperature Ta.

A compensation factor K may be calculated to determine how a pressurevalue needs to be modified. A pressure value sent to the gauge Pg may becalculated as follows:

Pg=Pt+K×ΔP

where Pg=gauge pressure, Pt=ambient temperature compensated pressure,K=compensation factor, and ΔP=Pmax−Ptmax, where Ptmax=Pt at maximumfilling.

A compensation factor K may be determined based the maximum fillingpressure Pmax, ambient temperature compensated pressure Pt, andthreshold value.

K=(Pt−threshold)/(Pmax−threshold)

When the deviation between the temperature compensated pressure Pt andmaximum filling pressure Pmax is zero, K=1. When the deviation betweenthe temperature compensated pressure Pt and the maximum filling pressurePmax is equal to the difference between Pmax and the threshold (e.g.Pt=threshold), K=0. So for example, if Pmax=3600 psi, threshold=3000psi, and Pt=3600 psi, K=1. If Pt=3400 psi, K=2/3. If Pt=3200 psi, K=1/3.If Pt=3000 psi, K =0.

In one example, suppose the tank is initially filled to a pressurevalue, e.g., 3600 psi. After the temperature drops, Ta=Ts, supposePmax=3600 psi, threshold=3000 psi, and Pt=3400 psi. If no gas has beenconsumed at this point, Ptmax=3400. Then the compensation factor can becalculated K=2/3. Pg=3400+(2/3)×(3600−3400)=approximately 3533 psi.After gas is consumed, Pt may drop to 3200 psi. ThenPg=3200+(1/3)×(3600−3400)=approximately 3267 psi. When Pt=3000 psi, K=0,and Pg=Pt.

When a time-based compensation is selected, a compensation is made basedon filling and reducing it by the time a key is on (e.g., vehicle enginehas started), a maximum time defined as a time constant, and a maximumvalue added to pressure defined as delta max %. In oneexample, Pg>Ptwhen time of key on<=time constant, and Pg=Pt when time of key on>timeconstant.

A time constant may be defined. The time constant may be provided inseconds, e.g., 1234 seconds as shown in FIG. 9, or any other unit oftime. The time constant may be entered by a user, or may beautomatically generated or based on a measurement. A default timeconstant may be provided. The time constant may represent the length oftime after maximum filling pressure is achieved. For example, fuel maybe provided into a tank and the pressure may rise until a maximumfilling pressure is achieved. After some time, even if no gas isconsumed, the pressure and/or temperature of the gas may decrease. Thetime constant may look at the length of time after the max pressure isachieved and during which a decrease occurs.

A delta max % may be defined. The delta max % may be provided as apercentage, e.g., 0% as shown in FIG. 9, or 25% in another example. Thedelta max % may be entered by a user, or may be automatically generatedor based on a measurement. A default delta max % may be provided. Thedelta max % may be a value that may be added to a Pt during a perioddefined by the time constant.

A pressure value provided to a gauge Pg may be defined under time-basedcompensation as follows:

Pg=Pt×(1+delta max %) while within time constant after max pressure

For example, if time constant=1234 seconds, and delta max=25%, whenPt=3400, Pg=3400×(1.25)=4250 psi and till 1234 seconds after key on,this percentage will be added. So if at t=1233 seconds, Pt=3000 psi,then Pg=3000*(1.25)=3750 psi, but just after t>1234 seconds, Pg=Pt.

In some embodiments, a compensation scheme may include using an idealgas law to determine the amount of fuel in a tank. Logic may be providedthat may include non-linear compressibility of gas. One or more otheralgorithm or calculation may also be performed to determine the amountof fuel in a tank. In some instances, ambient temperature may be afactor that may be used with preset logic to determine the output signalto the gauge. A look-up table or other records may be used for gaugelinearity correction. Alternatively, gain setting using interpolationmay be used. In some instances, a look-up table is not used fordetermining an output signal to a gauge. Using calculations based onphysical principles may advantageously not require the type ofcalibration that a look-up table would. For example, utilization ofalgorithms may not need special calibration since it is based on therelationship between amount of gas, temperature and pressure that mayremain true. The use of look-up tables instead of such calculations mayrequire look-up tables for every particular tank, sensor and maximumpressure by experiment.

In some instances, a D/A (digital to analog) converter may beimplemented using switched resistors. Such techniques may or may not beutilizing complex components. Such techniques may provide a result toderive resistor gauges.

Setting up a fuel gauge may also include selecting transfer functionspecifications 724. Setting up a transfer function specification mayinclude receiving one or more input from a user, and/or permittingautomated detection of one or more value. Such specifications mayreflect characteristics and/or parameters for gauges, and/or othersettings for compensation schemes and/or alerts for the vehicle.Selecting sensor specifications 726 may include receiving one or moreinput from a user and/or permitting automated detection of one or morevalue. Such specifications may reflect characteristics and/or parametersfor sensors. Selecting a service cycle 728 may permit an input from auser. The user may input a desired number of filling cycles to becompleted before providing an alert for a service. Additional detailsare provided elsewhere herein.

The ECU may be in communication with temperature sensors in and/or onone or more tanks, fuel management components present in the fuelsystem, fuel control components along plumbing lines and/or with one ormore ambient temperature sensors. The temperature sensors maydynamically provide the ECU with the temperature of the gas in the oneor more tanks, fuel management components, along plumbing lines and/orthe outside air temperature. The ECU may further be in communicationwith one or more pressure sensors of the disclosure. As described ingreater detail elsewhere herein, temperature compensation of thepressure measurement(s) may be provided to determine the final restingpressure after the gas cools during filling. As the fuel system cools toambient temperature, the system pressure may go down to a nominal fullpressure which is lower that the full pressure at the end of filling.The dynamic temperature measurements may enable the resting pressure tobe determined throughout the filling process. The determination of thefinal resting pressure based on the temperature provided by the dynamictemperature sensors may be utilized to initially fill the tanks to ahigher pressure, such that a resting pressure closer to a maximumallowable system pressure is achieved. This may allow more fuel to beprovided to the system during filling, thus extending the range ofdriving until the next refueling. Further, the dynamic temperaturesensors enable more accurate gauge readings (e.g., the gauge readingscan have better time resolution).

As described elsewhere herein, the ECU may be in communication with afilling station. For example, if the ECU is in communication with afiling station during filling, data regarding the resting pressureand/or instructions regarding target full pressure at the end of fillingmay be transmitted to the filling station. The ECU may communicate tothe filling station to fill the one or more tanks to a higher pressurethan the nominal full pressure. For example, the ECU may communicate tothe filling station to fill the one or more tanks to a higher pressurethan the nominal full pressure based on temperature compensation ofpressure enabled by the dynamic temperature sensor described previously.

FIG. 8 shows an example of an ECU 800 in communication with aninitialization device 810. As previously described, an ECU may beconnected to the initialization device via a wired connection.Alternatively, the ECU may be connected to the initialization devicewirelessly. The ECU may be connected to the initialization device over anetwork, such as a local-area network, or a wide-area network, such asthe Internet. The ECU may be connected to the initialization device overa telecommunications network, such as a cell phone or data network. Theinitialization device may be a mobile device (e.g., cell phone), or maybe controlled by a mobile device (e.g., cell phone). The ECU may beconnected to a single initialization device at a time. Alternatively,the ECU may be capable of connecting to a plurality of initializationdevices simultaneously.

An initialization device 810 may have a display 812. The display may becapable of displaying information. The display may be capable of showinga user interface, such as a graphical user interface. An example of auser interface is provided in FIG. 9 which is described furtherelsewhere herein. A display may be any display known in the artincluding, but not limited to, a cathode ray tube, a liquid crystaldisplay, a plasma screen, a touchscreen, a projection screen, an LEDscreen, or an OLED display.

The initialization device 810 may include one or more processor 814and/or memory 816. The processor may be capable of executing one or morestep. One or more steps may occur as dictated by one or more set ofrules. The rules may dictate when a user performs one or more steps, orwhen a machine automatically performs one or more steps. The rules maypermit automated electricity delivery management based on a set of oneor more conditions. The device may have memory that may includenon-transitory and/or tangible computer readable media which may containinstructions, logic, data, or code that may be stored in persistent ortemporary memory of the computer or other device, or may somehow affector initiate action by the computer or other device. The memory mayinclude one or more databases.

The initialization device may be capable of accessing remoteinformation, such as information stored in memory of the initializationdevice. The initialization device may access information stored inremote devices, such as servers, databases, and/or information providedon a cloud-computing based infrastructure. The initialization device maycomprise a communication unit that may be capable of communication withremote devices. Two-way communications may be provided. Suchcommunications may occur directly or over a network. Such communicationsmay be wired or wireless.

A user may be capable of interacting with the initialization device. Theuser may be capable of viewing information through the display. Thedevice may be capable of receiving an input from a user. The user mayprovide an input via a user interactive device including but not limitedto a keyboard, mouse, touchscreen, trackball, touchpad, joystick, wand,audio recognition device, gesture recognition device, optical sensors,or any other user interactive device. The user may be capable ofinputting one or more value that may be pertinent to the initializationand/or operation of the ECU. The initialization device may receive aninstruction from a user and/or remote device, or may generateinstructions, which may be provided to the ECU.

In one example, communications may be provided between the ECU and theinitialization device when one or more initialization step is performed.For example, a communication connection may be provided between the ECUand initialization device when setting up a fuel gauge, performingdiagnostics, checking a version of installed software, updating firmwareof the ECU, or any other initialization steps. In some embodiments,communications are established between the ECU and initialization devicewhen the vehicle is not in operation (e.g., key off), and not when thevehicle is in operation (e.g., key on). Alternatively, thecommunications may be established between the ECU and initializationdevice while the vehicle is in operation.

An initialization device may be provided separately from the ECU.Alternatively, in some embodiments, one or more features, components orfunctionalities of the initialization device may be incorporated withinthe ECU. For example, the ECU may include a display that may show a userinterface. A user may be capable of interacting directly with the ECU.The user may provide a user selection of a compensation scheme directlyto the ECU. Any description herein of an action performed by theinitialization device may be performed by the ECU. For example, the ECUmay comprise a communication unit that may be capable of communicationwith remote devices, such as servers, databases, and/or informationprovided on a cloud-computing based infrastructure. Two-waycommunications may be provided. Such communications may occur directlyor over a network. Such communications may be wired or wireless. The ECUmay be able to communicate with one or more filling stations, forexample, over a network, such as a telecommunications network (e.g., acell phone or data network). In some embodiments, the ECU maycommunicate with one or more other ECUs. A network of ECUs may have ahierarchical structure (e.g., a parent or master ECU may communicatewith one or more child or slave ECUs).

FIG. 9 shows an example of a user interface 900 for fuel gauge set-up inaccordance with an embodiment of the invention. The user interface maybe displayed on a display of an initialization device. The userinterface may be displayed during a fuel gauge set-up, such as duringthe fuel gauge set-up procedures or other initialization steps mentionedelsewhere herein.

The user interface 900 may include an option to select a COM port 910.In other embodiments, any sort of selection of a serial port, or portfor communication may be provided. In some instances, a default comport, such as COM 4 may be provided. After a COM port has been selected,the user may select an option to “Read.” If the power is not connected,an error may be provided. If a cable or other connector to theinitialization device is not connected, or a different COM number isbeing used, another error may be provided. If the initialization deviceand the ECU are properly connected, certain values, such as those withinthe transfer function 940 or sensor 950 groups may be automaticallyfilled in. Additional values may also be filled in.

The user interface 900 may include an option to select a fillingcompensation procedure 920. Any number of filling options may beprovided, which may include one or more, two or more, three or more,four or more, five or more, eight or more, or ten or more options.Examples of filling compensation procedures may include none,temperature, fuel, or time, as described in greater detail elsewhereherein. The user may select the desired compensation procedure from alist or group of options. An option may be provided for the user to“Start.” Additional information, such as parameter values (e.g., from astatus group 930) may be displayed. Examples of additional information,such as filename 992 and firmware version 994 may also be displayed.

A status group 930 may be displayed on the user interface. When a userselects an option to start, internal variables and/or sensor statusesmay be visible. For example, information from sensors, such as gaspressure (Ps), gas temperature (Ts), or ambient temperature (Ta) may bedisplayed. Additional information which may be calculated based onsensor values, selected options (e.g., filling compensation scheme),user-entered values (e.g., threshold), and/or any other additionalvalues, may be displayed (e.g., compensated gas pressure based onambient temperature (Pt), amount of pressure to be sent to the gauge(Pg), calculated signal for gauge (RV)).

The user interface may also provide the display of a transfer functiongroup 940. The transfer group may accept user inputs. In some instances,default values may be provided. Default values may be provided dependingon software, previously-entered values, information from sensors, and/orany other source. Descriptions of user-entered data may or may not haveinitial default values. A user may be able to set pressure values,resistor values, and/or voltage values. In some embodiments, the usermay enter values depending on the type of vehicle.

A user may also be able to set a threshold 960. The threshold value maybe useful for certain filling compensation schemes, as describedelsewhere herein. Gauge values to be displayed, above the threshold maybe compensated, while values below the threshold may be true values. Auser may also be able to select an alarm level 962. The alarm level setsthe low fuel warning lamp threshold in psi. For example, if the pressureof the tank drops below the alarm level, a warning light or other formof alert may be provided to an operator of the vehicle.

Another example of a user-selected value is a leakage on 964. Theleakage on value sets a maximum pressure reduction value in psi/hour forrun mode. For instance, a run mode may refer to when a vehicle is inoperation (e.g., key on). If the pressure value within a fuel tankdecreases at a rate (unit pressure/unit time) that exceeds the leakageon value, a leak may be detected. A warning, such as a blinking light,audio warning, or any other type of perceptible warning may be providedto an operator of the vehicle. A user may also select a leakage off 966value. The leakage off value may set the maximum threshold pressurereduction value in psi/hour for key off mode. For instance, a key offmode may refer to when a vehicle is not in operation (e.g., no keyturned in ignition). If the pressure value within a fuel tank decreasesat a rate (unit pressure/unit time) that exceeds the leakage off valuewhile the vehicle is not in operation, a leak may be detected. Awarning, such as a blinking light, audio warning, or any other type ofperceptible warning may be provided to an operator of the vehicle.

A time constant 968 value may be provided by a user. The time constantvalue may be useful for certain filling compensation schemes, asdescribed elsewhere herein. For instance, the time constant may be thetime in which compensation becomes zero in time mode. A delta max % 970may be entered by a user, and may be used in certain fillingcompensation schemes. The delta max % may be a maximum alloweddifference between true and compensated values in time mode.

A voltage output option may be provided. A user may or may not selectthe voltage output option. When selected, the gauge output may bevoltage type output. When unchecked, the gauge output may be resistancetype output.

A sensor group 950 may be displayed on a user interface 900. Sensorspecifications may be entered by a user. Examples of sensorspecifications may include pressure values and temperature values. Thesensors specifications may define any sensor range (e.g., if a customeror product needs 8,000 psi, a 8,000 psi pressure sensor may be chosen,and by putting 8,000 psi as the upper limit, the new sensor may bedefined to the ECU). A status may be displayed. The status may show thestatus of one or more sensor. For example, if no error is detected, thestatus may show OK. If an open circuit of a sensor is detected (e.g.,not connected properly with ECU), the status may indicate a circuit isopen. If a short circuit is detected, the status may indicate that ashort circuit exists.

A user interface may also include a service cycle group 980. A user maybe able to define a number of cycles of filling after which the ECU mayalert an operator of the vehicle to service the vehicle. A user maydefine the number of service cycles by entering a value and selecting a“write” option. A user may select a “read” function to see the currentcycle. A user may select a “reset” option to reset the count afterperforming a service. For example, a user may define that after 50filling cycles, the operator should get the vehicle serviced. The usermay be able to check and see that the vehicle is currently on cycle 33.Any type of visual display of the current filling cycle may be provided,to show how far along the vehicle is in the process. An alert to thevehicle operator may include a blinking light, audio alert, or any othertype of alert. In one example, an alert may be provided through the lowfuel warning lamp, but may blink at a specified rate. For example, thelow fuel warning lamp may show a steady light when the fuel level in thetank is low, may blink at a first rate when a leak is detected based onpressure drop, and may blink at a second rate when the time for servicehas arrived, or any combination thereof.

FIG. 10 shows an example of a method for displaying a fuel level usingan ECU. The ECU may be connected to a fuel gauge 1010. The ECU may alsobe connected to one or more sensors 1020. The ECU may be incommunication with the fuel gauge and sensors. The ECU may or may not bephysically connected to the fuel gauge and/or the sensors. The ECU maybe capable of connecting with various types of sensors and/or gaugeswhich may have different configurations. The ECU may be initialized,thereby setting up the ECU with selected sensors and/or gauges. The ECUmay be adaptable to work with different types of sensors and gauges. TheECU may be adaptable to operate with different vehicles or vehicletypes.

A filling compensation scheme 1030 may have been selected. The fillingcompensation scheme may have been selected from one or a plurality offilling compensation scheme options. Such options may include none,temperature-based compensation, fuel-based compensation, and/ortime-based compensation. Additional options may have been provided. Insome instances, only a single option may be selected. Alternatively aplurality of options may have been selected. In some embodiments, thefilling compensation may have been selected prior to operation of thevehicle (e.g., key on, turning the key in the ignition). Alternatively,a filling compensation scheme may be selected during or after theoperation of a vehicle. A default compensation scheme may be provided.

Based on input from one or more sensor, and/or a selected compensationscheme, a gauge command may be determined 1040. The gauge command may bedetermined by the ECU. The ECU may receive input from one or moresensor. For example, an ECU may receive information from a pressuresensor, capable of measuring pressure within a fuel tank, a temperaturesensor capable of measuring temperature of gaseous fuel within a fueltank, and/or an ambient temperature sensor, capable of measuring ambienttemperature. An ECU may receive information from sensors for a singletank, or from multiple tanks. The ECU may have received an input for aselected filling compensation scheme. The ECU may have received thecompensation scheme prior to operation of the vehicle. The ECU may havea selected compensation scheme stored therein. The selected compensationscheme may be stored in a memory of the ECU. The compensation scheme mayinclude one or more algorithm or instructions for providing a gaugecommand.

The ECU may perform one or more calculation in accordance with thecompensation scheme. The calculation may incorporate one or more sensorvalues. Examples of such calculations and further descriptions ofcompensation schemes, such as none, temperature-based compensation,fuel-based compensation, and/or time-based compensation, are providedelsewhere herein. The gauge command may be determined based on one ormore calculation. For example, a gauge pressure (e.g., Pg) may becalculated. Based on the calculated gauge pressure, one or more gaugecommand may be provided to the gauge. Examples of gauge commands mayinclude one or more voltage value provided to a gauge, and/or any othersignals provided to the gauge.

The gauge may be driven in accordance with the command 1050. The gaugemay be driven to display a fuel level. The fuel level may be dependenton a gauge pressure Pg that may be calculated. For example, for a higherPg value, a higher fuel level may be displayed on a gauge. Driving thegauge may include causing the gauge to display a value, whether it isthrough a digital or electronically powered display, or a mechanicaldisplay with a movable part.

The fuel level may be displayed during operation of a vehicle. Forexample, a vehicle operator, such as a driver, may power the vehicle on(e.g., by inserting a key into the ignition or any other vehiclepowering mechanism known in the art). When the vehicle is on, the gaugemay display the fuel level of the vehicle. When the vehicle is poweredon, the ECU may determine a gauge command based on sensor input andselected compensations scheme. The ECU may provide a signal to a gaugethat may display the fuel level to the vehicle operator. The fuel levelmay vary during the operation of the vehicle.

In some embodiments, the fuel level is not displayed when the vehicle isnot in operation. Alternatively, the fuel level may be displayed whenthe vehicle is not in operation.

One or more alert may be provided to an operator of the vehicle. Thealert may be provided while the vehicle is in operation. In someinstances, an alert may be provided even when a vehicle is not inoperation. For example, an alert may be provided when the fuel is low.This may be detected when a pressure drops below a threshold value. TheECU may receive the sensor signal for pressure and may or may notcompensate based on one or more compensation scheme. The ECU may have athreshold value, and may determine whether the pressure of the fuel hasdropped below the threshold.

Another example of an alert may be when a leak is detected. A leak maybe detected when the rate of pressure decrease exceeds a leakagethreshold. For example, if the pressure drops by more than a certainpressure unit/time unit (e.g., psi/hour), this may indicate a leakand/or an alert may be provided. In some instances, different leakagethresholds may be provided for when a vehicle is in operation (leakageon threshold) and for when a vehicle is not in operation (leakage offthreshold). In some instances, during vehicle operation, some pressuredecrease may be expected as fuel is consumed. The leakage on thresholdmay be higher than the leakage off threshold to compensate for theexpected pressure drop in fuel when a vehicle is in operation. Forexample, a leakage on value may be about 1500 psi/hour while a leakageoff value may be about 150 psi/hour. Alternatively, the same value maybe provided as a leakage threshold, regardless of whether the vehicle isor is not in operation.

An alert may optionally be provided when a threshold number of fillingcycles have been completed for the vehicle. The alert may be provided tothe operator of the vehicle to get the vehicle serviced. For example, aselected number of filling cycles (filling the vehicle with fuel) may beselected.

In some embodiments, the ECU may determine when one or more filters(e.g., on the vehicle engine, on one or more fuel management componentspresent in the fuel system, etc.) may need to be replaced or serviced.The ECU may notify the vehicle computer, the driver, or other on-boardsystem. For example, the ECU may communicate filter changes to one ormore gauges described herein, such as a vehicle dashboard. In anotherexample, the ECU may cause a warning lamp to turn on to indicate that afilter change is needed. In some examples, the ECU may communicate withone or more controls on the vehicle, such as a valve that may allow aflow path with a used filter to be bypassed. The ECU may communicate theneed for filter service externally to a filling station, central server,or fleet management software.

Filter monitoring may be accomplished by various means including, butnot limited to, providing pressure sensors before and after the filterin a flow path comprising the filter and measuring the difference inpressure, keeping a log of the amount of fuel that has passed throughthe filter, or by counting the number of fillings. More details on thecalculation of the number of fillings are provided elsewhere herein.

During filling, the vehicle may be turned off (e.g., engine off and allauxiliary systems off). When the vehicle is turned off, the ECU may notbe powered on. Further, one or more sensors, gauges, controls and/orother ECUs may not be powered on. If the ECU is not powered on andsensor data cannot be directly observed during the fill, it may benecessary for the ECU to compare the state of the system at power on tohow it was during the last power off. By comparing the pressure, thetemperature, the state of a reed/proximity switch and/or other sensorsor indicators, the ECU can determine if the vehicle was filled and byhow much. Alternatively, portions or all of the ECU may be powered onduring filling. For example, a key position/setting of the vehicleignition may be provided specifically to allow for ECU to be keptpowered on during filling. In some cases, the ECU may remain powered onfor a predetermined amount of time (e.g., 20 minutes) after the vehicleis turned off.

Embodiments of the invention may provide an alternate fuel path forlower pressure operation. As described in greater detail through thedisclosure, the gaseous fuel containing device may contain fuel storedat a high pressure, and may provide the pressurized fuel to a vehicleengine. As fuel is provided to the engine, fuel in the gaseous fuelcontaining device is consumed and the fuel pressure drops. In somecases, such as, for example, when the high pressure system gets to about2× or 3× the minimum operating pressure (wherein the minimum operatingpressure may be the pressure required to ensure adequate fuel flow fromthe gaseous fuel containing device to the engine), starting and/oroperating issues may occur. The starting and/or operating issues may bedue to designing the fuel path to the engine for high pressureoperation. Thus, there is a need to have a separate fuel path for lowpressure operation.

The fuel path during low pressure operation may be specifically designedto deliver adequate fuel flow to the engine when the pressure (oramount) of fuel in the gaseous fuel containing device (e.g., tank)decreases to a predetermined value. For example, the low pressure fuelpath can be designed for <750 psi operation. The components of the lowpressure fuel path may or may not be designed for high pressureoperation (e.g., 3600+ psi operation). For example, the low pressurefuel path may be able to withstand high fuel pressure. Alternatively,the low pressure fuel path may not be able to withstand high fuelpressure, and may only be operated when the pressure in the fuel tank(and the remainder of the fuel system) falls below a certain thresholdvalue. In some examples, only a portion of each flow path (e.g., aregulating portion, described next) may be specifically designed for lowpressure operation, while the rest of the fuel path may be identicalduring both low and high pressure operation. In other examples, one ormore parallel or switchable flow paths may be provided along the fuelflow path.

In one example, a low pressure fuel path may be provided by placing tworegulators, of which one is a high pressure regulator and one is a lowpressure regulator, in parallel with each other. The high and lowpressure flow paths may be outfitted with electronic solenoid valvesand/or pressure sensors before, after, or both before and after eachregulator. When the system pressure gets below a certain threshold, thesystem may route the fuel to the low pressure path. By enabling loweradequate fuel flow to the engine at lower fuel system pressures, vehicleoperation before the next refueling may be extended through improvedutilization of fuel carried on board the vehicle (i.e., more fuel can beextracted from the tanks since the fuel can continue being extracteddown to lower tank pressures). Various combinations or alternativeconfigurations of the above components or of similar components in theart may be used to implement the two paths.

The system may be following instructions provided by the ECU. Forexample, the ECU may receive temperature, pressure and/or other sensordata and may provide a signal to the one or more solenoid valves to openor close to control (e.g., close or open) appropriate fuel paths.

Further alternative embodiments of the low pressure fuel path mayinclude outfitting the high pressure fuel path (e.g., a first tankoutlet, such as a first outlet of a tee connector) with a valve or otherflow control component that automatically closes below a predeterminedinlet pressure. The low pressure fuel path (e.g., a second tank outlet,such as a second outlet of a tee connector) may be outfitted with avalve (e.g., reverse acting valve) or flow control component of oppositefunctionality, i.e., that automatically opens below a predeterminedinlet pressure. In this configuration, the alternate fuel paths may ormay not be controlled by the ECU.

In some embodiments, one or more fuel tanks or gaseous fuel containingdevices may be provided on the vehicle. When more than one tank isprovided, one or more of the tanks may be controlled by the ECU toenable staged fuel delivery of the fuel stored in the tanks. Forexample, the ECU may control one or more electronic solenoid valves. TheECU may receive data from one or more pressure/temperature sensors.These solenoid valves and pressure/temperature sensors may be provided,for example, on a neck of each tank, on one tank (e.g., on the body, oron the neck), on a combination of tanks (e.g., on two of a plurality oftanks, on all tanks, etc.), or elsewhere in the system. For example,with solenoid valves and pressure/temperature sensors on the neck ofeach tank, the ECU may close some tanks off and keep others open duringoperation. Tanks may be actively opened, actively closed, kept open orkept closed by the ECU. In some cases, one or more solenoid valves maybe provided separately from one or more pressure/temperature sensors oneach tank. Some tanks may have either solenoid valve(s), orpressure/temperature sensor(s). In some cases, a majority of tanks mayhave pressure/temperature sensor(s), while only some tanks may havesolenoid valve(s). Alternatively, solenoid valve(s) may be provided onall tanks, but only a subset of the valve(s) may be controlled by theECU for staged fuel delivery. Each tank may have one or more of asolenoid valve, a pressure sensor or a temperature sensor.

In some embodiments of a multiple tank system, the tanks may be used onetank at a time. For example, one tank may be used only for starting orcranking, and the rest of the tanks may be used for driving operation.In this configuration, one tank or a subset of tanks may be maintainedat high pressure, which may prevent the previously described issues withlow pressure starting. Alternatively, fuel may be consumed from one tankor a subset of tanks at a time. The ECU enables switching between tanksat any time during operation. Similarly, the ECU, if utilized duringfilling, may also enable controlled filling of the tanks. For example,tanks may not need to be accessed one at a time, but a unified fuelinlet controlled by the ECU may be used to fill all tanks. In somecases, tanks may be filled or drained according to a predefined scheduleor settings. The predefined schedule or settings may be set by the user,automatically controlled by the ECU, or a combination thereof.

By utilizing the tanks in a staged configuration, it is possible to savetime and energy refueling if the tanks are not completely drained. Forexample, if there is a five tank system, the tanks were being consumedsequentially and only two of the five tanks have been drained, then thestation will only need to fill two tanks up to full pressure.

The ECU may further control high and low pressure fuel paths provided onone or more of a plurality of tanks during staged fuel delivery. Forexample, high and low pressure fuel paths may be provided on each tank.Alternatively, for example when some tanks are used only for highpressure operation during starting and some tanks are used only forvariable pressure operation during driving, the starting tanks may onlybe provided with a high pressure path, while the driving tanks may beprovided with the high pressure and low pressure paths. Each tank mayhave one or more of a solenoid valve, a pressure sensor or a temperaturesensor. Alternatively, the tanks may share one or more sensors and/orsolenoid valves. The sensors, solenoid valves and/or other tankcomponents may be individually controlled by the ECU. Alternatively, theECU may simultaneously control groups of sensors, solenoid valves and/orother tank components on multiple tanks.

In some embodiments, one or more kill caps may be provided. If one ormore specified operational condition is detected, a starter interruptcircuit may prevent a vehicle from being started. For example, during afilling procedure while a fuel dispenser is connected to a vehiclereceptacle (e.g., fluidically connected to a vehicle tank), the starterinterrupt logic may cause the one or more kill caps to kill aconnection, preventing the starting the vehicle. The kill caps may beswitches that may kill the connection. For example, if a driver of thevehicle were to forget to disconnect the dispenser and drive thevehicle, an explosion may occur. However, with the kill caps safetymechanism, the driver can not start the engine while the fuel dispenseris connected to the vehicle (e.g., like pressing the clutch pedal tostart a standard transmission vehicle). The starter interrupt may becontrolled without the use of relays, which can create voltage spikes inthe electrical system. In some embodiments, a plurality of kill switchesmay be provided. For example three or more kill switches may beprovided. The kill switches may be provided at different points orlocations of the vehicle. One kill switch may be provided to check adust cap on a vehicle receptacle. Another kill switch may be provided atthe vehicle receptacle. Another kill switch may be provided for a fillpanel door. Additional or alternative configurations of kill switchesare possible, for example, as provided in U.S. Provisional PatentApplication Ser. No. 61/612,902 (“IGNITION DISCONNECT”), filed Mar. 19,2012, which is incorporated herein by reference in its entirety.

In some embodiments, the ECU may monitor the life of one or more gaseousfuel containing devices (fuel tanks) on a vehicle. The ECU may be ableto determine when a fuel tank (gaseous fuel containing device) will needto be replaced or serviced. The ECU may notify a vehicle computer,driver (e.g., via a gauge, dashboard, or warning lamp) or other on boardsystem or entity described herein. The ECU may communicate the need fortank service externally to a filling station, a central server, fleetmanagement software, or other external entity described herein.

In some cases, the life of the tank and/or the amount of time betweentank inspections may be a fixed number of years. This may not take intoaccount the amount of stress and/or the type of stress that the tank hasbeen subjected to over its lifetime. The determination of tank life maybe improved by utilizing one or more sensors on the tank, including, butnot limited to, pressure, temperature, strain, acceleration, proximity,reed switch and/or light sensors. The sensors may be in communicationwith the ECU and may transmit data to the ECU. The data from the sensorsmay be logged with a time stamp. Using the time stamped sensor data, theamount of stress each tank has been under may be determined usingvarious models. The stress calculation may be executed on board (e.g.,by the ECU), on a central server or other remote information system ordevice (e.g., by sending the collected data by any of the communicationmeans described herein), or a combination thereof. Using the amount ofstress that the tank has been exposed to over its lifetime may provide amore accurate measure for determining when the next service should beand/or the overall lifespan of each tank in the system.

The sensor data, the calculated stress, the determination of the tanklife and/or other associated data may be transmitted to a fillingstation in order to prevent filling of a tank that may not be in acondition to be filled. For ea example, the data may be communicated tothe filling station in order to prevent the filling of an uninspectedtank (e.g., a tank for which damage or stress was detected, and whichmay need to be inspected and/or replaced before being fit for service).The data may be communicated, for example, from the ECU or from theremote information system or device on which the stress and/or tank lifecalculation was executed.

Embodiments of the invention may include electronic witness systems. TheECU may observe the current state of the fuel and/or vehicle system, forexample via one or more sensors, and may communicate the system statusto the driver, the vehicle, fleet software, a filling station, or anyother on board or external entity described herein. The status of thesystem may include, for example, preventative maintenance information,real-time electronic witness data, or other system data. The electronicwitness data may include, but is not limited to, tank or body coverdamage detection, temperature and pressure data, data from strain gaugesand data from a G-ball or other acceleration sensor.

In some cases, the ECU may be able to detect if damage was done to atank or body cover from a very thin conductive inlay into the body coverpanels. If the circuit of the conductive inlay is broken, the ECU maycommunicate to the vehicle, the driver, fleet software, a fillingstation, or any other on board or external entity described herein thatdamage has been done to a body cover. Communication of the electronicwitness data may ensure timely inspection of the damage. The electronicwitness systems may be provided on one or more tanks, on one or moretank covers, or elsewhere within the vehicle. Examples of electronicwitness systems utilized for gaseous fuel containing devices areprovided in U.S. Provisional Patent Application Serial No. 61/613,933(“SMART COVERS”), filed Mar. 21, 2012, which is incorporated herein byreference in its entirety. The electronic witness functionality may notbe limited to the vehicle fuel system. For example, the electronicwitness functionality may be applied on an engine cylinder, on thevehicle chassis, or in other locations on the vehicle.

The electronic witness functionality may include communication of theECU with strain gauges or other sensors on critical components that candetermine damage or stress on the critical components. The ECU may usepressure and temperature data to determine if there was a fire or anaccident. In the case of a fire or an accident, the ECU may notify oneor more entities described in more detail elsewhere herein that a tankservice or an inspection is needed. The ECU may communicate with aG-ball or other acceleration sensor that can determine if an accidenthas occurred. In response, the ECU may adjust vehicle operation by, forexample, turning off electronic solenoids at tanks to prevent fuel loss.In another example, the ECU may notify a station, a driver or any otherentity described herein that an inspection is necessary before the nextrefueling. The ECU may activate an alarm (e.g., an alarm on a gauge or adashboard, a warning lamp) when triggered one or more electronic witnesssystems. Alternatively, or additionally, the ECU may notify a fleetservice provider or fleet manager during minor (non-critical) events.

The electronic witness functionality may interact with one or morefunctionality in accordance with the present disclosure. For example, anelectronic witness system on a fuel tank or body cover may communicatewith the ECU that damage has occurred, The ECU may then communicatewith, for example, an ignition disconnect or kill switch system toswitch off ignition. In some cases, as described in greater detail withreference to FIG. 11, the electronic witness system may communicatedirectly with the ignition disconnect system or with any other entity incommunication with the ECU or otherwise provided on the vehicle.

FIG. 11 shows examples of entities with which an ECU 1100 maycommunicate. Such entities include one or more sensors 1101 (e.g.,temperature sensors, pressure sensors, electronic witness sensors or anyother sensors described herein), one or more gauges 1102 (e.g.,readouts, including mechanical needle readouts, user interfaces,indicator lamp, vehicle dashboard or any other gauges or indicatorsdescribed herein), one or more controls 1105 (e.g., kill switches orkill caps, valves, tanks or tank components, tank or body covers orcomponents thereof, or any other controls described herein), one or moreECUs 1104 (e.g., ECU associated with a kill cap or a body tank/bodycover, ECU associated with engine manifold, or any other ECUs describedherein), and/or one or more devices or information systems hosted ondevices 1103 (e.g., initialization device, server, cloud, fillingstation, fleet management software, or any other device or informationsystem hosted on a device described herein). The entities with which theECU interacts may interact with each other. In some examples, one ormore of the entities may interact with the ECU by proxy (e.g., viaanother entity). Further, one or more entities such as an electronicwitness may function both as a sensor and as a control. For example, insome cases, an electronic witness component may communicate data orinformation to the ECU. In other cases, or additionally, the ECU mayprovide instructions or send data to the electronic witness component(e.g., the ECU may trigger an electronic witness circuit in response toan event elsewhere in the system that was communicated to the ECU).Further variations include functionality of a control system as a gauge,and so on. One or more entities may be located on board the vehicle(e.g., gauges, sensors, controls, other ECUs).

One or more entities may be located externally to the vehicle (e.g.,gauges, devices). For example, a filling station is external to thevehicle and may be in communication with the vehicle's ECU. In someexamples, sensors or controls may also be located externally to thevehicle, such as, for example, an external sensor in communication(e.g., wirelessly) with the ECU during filling, or an external control(e.g., fuel pump) in communication with the ECU during filling, etc.Thus, the entities in FIG. 11 may communicate with the ECU, with eachother, interchangeable and/or by proxy. The entities in FIG. 11 may belocated on the vehicle or externally to the vehicle.

Any of the entities in communication with the ECU may utilize anycommunication types and interfaces, connection types and interfaces,set-up interfaces, initialization interfaces, user interfaces, andassociated methods described in detail elsewhere herein. Thus, forexample, a communication interface for an initialization device may beutilized for providing a communication interface for another ECU, acommunication type used for communicating with an initialization devicemay be utilized to communicate with a filling station, and so on.

The ECU may communicate with other devices, sensors, gauges, ECUs, andthe vehicle (including components/systems and controls on board thevehicle). The ECU may communicate to other electronic devices andsensors both on the vehicle and to external servers, devices,filling/fueling stations and/or other entities using one or morecommunication protocols and via one or more type of connection. Forexample, the ECU may communicate using either passive or active RFID,Wi-Fi, Blue Tooth, or other wireless communication methods, or over adirect wire connection such as, for example, USB, Ethernet, Firewire,serial, or single wire, etc. The ECU may send and receive data to andfrom the ECU using the CAN protocol or other vehicle communicationprotocol, or to external computers, servers, or devices using a numberof communication protocols including, for example, TCP/IP, serial, USB,or other communication method. The ECU may also receive inputs from thevehicle, such as, for example, speed, distance traveled, amount of timeinjector was open, fuel consumption, etc. The ECU may communicate dataor signals to fueling station, the vehicle dashboard or other devices orinformation systems hosted on devices. In some embodiments, the ECU maybe able to communicate or partially communicate while the vehicle isturned off (e.g., filling). Power to the ECU during such operation maybe supplied, for example, from one or more auxiliary power sources onboard the vehicle (e.g., a battery) or one or more power sourcesexternal to the vehicle in electronic communication with the ECU and/orthe vehicle via a wired or wireless power connection.

The ECU may log all data from all systems on board the vehicle. The ECUmay communicate with all systems on board the vehicle. The ECU maycommunicate with systems external to the vehicle. Examples of datatransmitted may include the vehicle identification number (VIN), licenseplate, vehicle model, tank configuration, number of tanks, fleet vehiclenumber, system serial number, system status, number of fill cycles,filter service and tank service data, sensor data, temperature data, orany other data that has been collected or observed. Diagnostics may becommunicated to and from the ECU (e.g., via the CAN protocol) andintegrated into the vehicle's error codes. These error codes may betransmitted to external electronics, fleet software, servers, thedriver, etc.

Vehicle data collected in other systems (e.g., other ECUs or controls),such as, for example, speed or distance traveled, may be sent to the ECUand used in calculations along with data the ECU collects via itssensors or other communication channels. These calculations may include,but are not limited to, average fuel consumption per mile, instantaneousfuel consumption, total range left before the next refueling, etc.

The transmitted data may be uploaded to fleet tracking software for easyintegration into vehicle maintenance tracking, fuel consumptiontracking, vehicle fuel efficiency tracking in miles per gallon Dieselequivalent (MPGDe), vehicle efficiency tracking in cost per mile($/mile), and/or other parameters. Service data (e.g., filter changes,tank life data, damage detected by electronic witness systems) may besent to a central server where replacement parts can be purchased andservice or warranty requests can be sent. The warranty and/or servicerequests may be sent along with data that has been logged while theproblem was occurring, thus enabling fast diagnosis. In some examples,autonomous diagnosis may be enabled.

In some embodiments, the ECU may enable data logging and acquisition.The ECU may collect data from various sensors and store the data with atimestamp of when the data was collected. The data may be processed onboard (e.g., by the ECU), on a central server in communication with theECU after it has been transmitted via methods discussed earlier, or acombination thereof. The data may be stored in memory and/or transmittedin either a compressed or raw data form. The data may take the form ofaggregate data to minimize memory storage size. The data may be raw datafrom all sensors. The data may be able to be streamed in real time andobserved on either a display inside the vehicle, on a computer ordisplay directly connected to the ECU, on a computer or display inremote communication with the ECU or via any othercommunication/connection method described herein.

One or more characteristics, components, features, and/or steps known inthe art may be incorporated and/or used. See, e.g., U.S. Pat. No.5,379,637 and U.S. Pat. No. 6,957,171, which are hereby incorporated byreference in their entirety.

It should be understood from the foregoing that, while particularimplementations have been illustrated and described, variousmodifications can be made thereto and are contemplated herein. It isalso not intended that the invention be limited by the specific examplesprovided within the specification. While the invention has beendescribed with reference to the aforementioned specification, thedescriptions and illustrations of the preferable embodiments herein arenot meant to be construed in a limiting sense. Furthermore, it shall beunderstood that all aspects of the invention are not limited to thespecific depictions, configurations or relative proportions set forthherein which depend upon a variety of conditions and variables. Variousmodifications in form and detail of the embodiments of the inventionwill be apparent to a person skilled in the art. It is thereforecontemplated that the invention shall also cover any such modifications,variations and equivalents.

1. (canceled)
 2. A gaseous fuel management system comprising: aplurality of different fuel gauges or sensors; an electronic controlunit (ECU) in communication with each of the plurality of fuel gauges orsensors, wherein the electronic control unit is configured to adapt andcompensate for different intrinsic characteristics or configurations ofthe plurality of gauges or sensors, by selecting an appropriate fuellevel compensation scheme from a plurality of different fuel levelcompensation schemes when setting up a selected fuel gauge selected fromthe plurality of different fuel gauges, that enables a compensated fuellevel to be displayed on the selected fuel gauge during or after a fillevent.
 3. The system of claim 2, wherein the sensors comprise one ormore temperature sensors and pressure sensors.
 4. The system of claim 2,wherein the fill event comprises partially or completely filling a fueltank with a gaseous fuel, wherein the fuel tank is operably coupled tothe selected fuel gauge.
 5. The system of claim 4, wherein the pluralityof different fuel level compensation schemes comprises a compensationscheme based on a detected filling speed of the fuel tank.
 6. The systemof claim 5, wherein one or more of the sensors and the ECU areconfigured to detect the filling speed of the fuel tank, by directlymonitoring a pressure of the fuel tank throughout the fill event andmonitoring a duration of the fill event.
 7. The system of claim 5,wherein one or more of the sensors and the ECU are configured to detectthe filling speed of the fuel tank, by measuring a temperature and thepressure of the gaseous fuel within the fuel tank after the fill event,measuring an ambient temperature outside of the fuel tank, and using amodel to calculate a duration of the fill event based on the measuredtemperatures and pressure.
 8. The system of claim 5, wherein one or moreof the sensors and the ECU are configured to detect the filling speed ofthe fuel tank, by using a time constant that reduces a temperature ofthe gaseous fuel within the fuel tank to an ambient temperature outsideof the fuel tank.
 9. The system of claim 8, wherein the time constant isinput to the ECU by a user, or comprises a default value that is storedin the ECU.
 10. The system of claim 4, wherein the appropriate fuellevel compensation scheme is selected from the plurality of differentfuel level compensation schemes after completion of the fill event and avehicle comprising the fuel tank is in operation.
 11. The system ofclaim 4, wherein the plurality of different fuel level compensationschemes comprises a time compensation scheme that determines an amountof time for the fuel tank to cool to ambient temperatures aftercompletion of the fill event that causes the fuel tank to heat up. 12.The system of claim 4, wherein the gaseous fuel comprises natural gas orcompressed natural gas (CNG).
 13. The system of claim 2, wherein one ormore of the plurality of different fuel level compensation schemescomprises logic that is not based on ideal gas law.
 14. The system ofclaim 4, wherein one or more of the plurality of different fuel levelcompensation schemes comprises logic that compensates for non-linearityof gas compressibility within the fuel tank.
 15. The system of claim 2,wherein the plurality of different fuel level compensation schemes areconfigured to account for different compositions and properties ofdifferent types of gaseous fuels that are filled into one or more fueltanks.
 16. The system of claim 4, wherein the plurality of differentfuel level compensation schemes are configured to account for differentcompositions and properties of the natural gas or CNG that is filledinto the fuel tank.
 17. The system of claim 14, wherein the ECUcomprises memory comprising non-transitory computer readable media forstoring the plurality of different fuel level compensation schemes. 18.The system of claim 17, wherein the memory comprises one or more look-uptables for compensating the non-linearity of gas compressibility withinthe fuel tank.
 19. The system of claim 18, wherein the one or morelook-up tables are experimentally determined for different types of fueltank, different types of gauges, and different types of sensors.
 20. Thesystem of claim 18, wherein the one or more look-up tables are used tocorrect a gauge linearity of each of the plurality of fuel gauges.